The currently used vaccine for tuberculosis is M. bovis BCG. This live vaccine strain gives protection against TB meningitis in children, but is also used as a treatment for bladder cancer (in combination with surgery). We are using different approaches to improve the functioning of the BCG vaccine. One of these approaches is to employ T7S to secrete heterologous substrates which will improve the response of the immune system during anti-TB vaccination or in cancer therapy. These improved BCG strains are tested in a murine bladder cancer model or murine vaccination model.